The president wanted to take Jerome Powell, the Fed chair, to task over the cost of renovations to the central bank’s headquarters, but Mr. Powell was having none of it.

The president’s participation in a tour of the Fed had the makings of a public relations disaster for the central bank. But by Friday, the president was praising Powell.

President Trump’s unprecedented walk-through of the Federal Reserve’s now-controversial building renovation project with Jerome Powell ended with a sign of relief for the central bank chief who’s been under pressure for months to slash interest rates.